💤

Nap Calculator

Find the best time and length for a refreshing nap — without ruining tonight's sleep.

Nap Calculator

Enter the current time to see the best window for a refreshing power nap or a full-cycle nap.

Keep naps before 3 PM and under 90 minutes to protect nighttime sleep.

How the nap calculator works

A nap calculator takes the current time and adds your natural 90-minute sleep cycle — plus about 15 minutes to fall asleep — to show two useful targets: a 20-minute power nap and a 90-minute full-cycle nap. Both avoid deep sleep, so you wake clear instead of groggy.

If you have asked “when should I nap?”, the short answer is early afternoon. A nap that lands you in deep sleep, or one taken late in the day, steals from the night. This tool keeps you in the safe window.

Power nap vs full-cycle nap

A 20-minute power nap is a quick reset — boosted alertness with no sleep inertia. A 90-minute nap lets you complete one full cycle and wake at a light-sleep boundary, which feels more like genuine rest. Pick the one your schedule allows, and keep it before about 3 PM.

A few quick tips

  • Nap before 3 PM to protect bedtime.
  • Keep it under 90 minutes unless you can full-cycle.
  • Use a dark, cool space so you actually fall asleep.

Frequently asked questions about the Nap Calculator

Everything you need to nap smart.

Explore more sleep tools